I don't think they are a scam. I have used them twice at least in Belgium and Germany when their offer was cheaper than the competition. The worst thing that happened was that the room was sold as tax included, but of course the Brussels room tax had to be paid to the hotel on the spot in addition. While this is fraud in the strict sense, it happens in Brussels all the time on all sites. I have no idea how their business model works and I am not to defend them. But I guess the author was just the victim of a "normal" mess-up with more rooms given to various booking systems in total than available in reality. And of course poor customer service which is standard for most companies doing business on the internet.